Perfusion Mapping of Flaps Using Indocyanine Green Fluorescence Angiography and Laser Speckle Contrast Imaging.

Background: Indocyanine green fluorescence angiography (ICG-FA) is often used for assessing tissue circulation in reconstructive surgery. Indocyanine green (ICG) is injected intravenously and visualized in the tissue with an infrared camera. The information is used to plan the surgery, for example, in free flap breast reconstructions. Laser speckle contrast imaging (LSCI) is another method that uses laser to assess tissue perfusion in the skin. Unlike ICG-FA, LSCI is noninvasive and may therefore have an advantaged compared with ICG-FA. The aim of this study was to evaluate the correlation between information obtained from these two techniques. Methods: Five deep inferior epigastric perforator patients were included. The flaps were assessed with LSCI and ICG-FA. For LSCI, the perfusion was calculated in 32 regions of interest. For ICG-FA, the maximum slope and area under curve (AUC) were calculated based on average pixel intensity data. Results: Large variations in maximum slope values could be seen between flaps, whereas AUC had lower variability within the same flap and between flaps. Pearson rank correlation comparing average perfusion (LSCI) and AUC (ICG-FA) showed a correlation between the values (r = 0.55, P < 0.0001). No significant correlation was observed between perfusion and maximum slope (r = 0.11, P = 0.18). Conclusions: There is a significant correlation between data obtained using LSCI and ICG-FA, when ICG-FA data are presented as AUC of the ICG-FA intensity curve. Maximum slope lacks significant correlation with flap data obtained with LSCI. The study indicates that LSCI may be used in reconstructive surgery to assess tissue circulation in a way similar to ICG-FA.

Muscle preservation in proximal nerve injuries: a current update.

Optimal recovery of muscle function after proximal nerve injuries remains a complex and challenging problem. After a nerve injury, alterations in the affected muscles lead to atrophy, and later degeneration and replacement by fat-fibrous tissues. At present, several different strategies for the preservation of skeletal muscle have been reported, including various sets of physical exercises, muscle massage, physical methods (e.g. electrical stimulation, magnetic field and laser stimulation, low-intensity pulsed ultrasound), medicines (e.g. nutrients, natural and chemical agents, anti-inflammatory and antioxidants, hormones, enzymes and enzyme inhibitors), regenerative medicine (e.g. growth factors, stem cells and microbiota) and surgical procedures (e.g. supercharge end-to-side neurotization). The present review will focus on methods that aimed to minimize the damage to muscles after denervation based on our present knowledge.

The research question: the What, Why and How in hand surgery.

Identifying a good research question is one of the most important steps when laying the foundation of a research project. A good research question can aim to answer a hotly debated clinical issue, challenge a pre-existing dogma or make a contribution to specific aspects of a broader field of study. The difficulty in defining the question lies with pinpointing an important research topic or an area that is characterized by a lack of knowledge (the What), grasping the significance of how a precisely defined study can potentially impact on clinical practices (the Why) and determining the optimal study design tailored to answer the specific question (the How). These three domains constitute pivotal concepts in the process of shaping the research question.

Skin perfusion and oxygen saturation after mastectomy and radiation therapy in breast cancer patients.

The pathophysiological mechanism behind complications associated with postmastectomy radiotherapy (PMRT) and subsequent implant-based breast reconstruction are not completely understood. The aim of this study was to examine if there is a relationship between PMRT and microvascular perfusion and saturation in the skin after mastectomy and assess if there is impaired responsiveness to a topically applied vasodilator (Methyl nicotinate - MN). Skin microvascular perfusion and oxygenation >2 years after PMRT were measured using white light diffuse reflectance spectroscopy (DRS) and laser Doppler flowmetry (LDF) in the irradiated chest wall of 31 women with the contralateral breast as a control. In the non-irradiated breast, the perfusion after application of MN (median 0.84, 25th-75th centile 0.59-1.02 % RBC × mm/s) was higher compared to the irradiated chest wall (median 0.51, 25th-75th centile 0.21-0.68 % RBC × mm/s, p < 0.001). The same phenomenon was noted for saturation (median 91 %, 25th-75th centile 89-94 % compared to 89 % 25th-75th centile 77-93 %, p = 0.001). Eight of the women (26%) had a ≥10 % difference in skin oxygenation between the non-irradiated breast and the irradiated chest wall. These results indicate that late microvascular changes caused by radiotherapy of the chest wall significantly affect skin perfusion and oxygenation.

Microcirculatory changes in the skin after postmastectomy radiotherapy in women with breast cancer.

Postmastectomy radiotherapy (PMRT) increases the risk for complications after breast reconstruction. The pathophysiological mechanism underlying this increased risk is not completely understood. The aim of this study was to examine if there is a relationship between PMRT and microvascular perfusion in the skin directly after, and at 2 and 6 months after PMRT and to assess if there is impaired responsiveness to a topically applied vasodilator (Methyl nicotinate-MN) after PMRT. Skin microvascular responses after PMRT were measured on two sites in the irradiated chest wall of 22 women before, immediately after, and at 2 and 6 months after unilateral PMRT with the contralateral breast as a control. A significant increase in basal skin perfusion was observed in the irradiated chest wall immediately after RT (p < 0.0001). At 2 and 6 months after RT, there was no longer a difference in basal skin perfusion compared to the contralateral breast and compared to baseline. Similarly, the blood flow response in the skin after application of MN was stronger immediately after RT compared to before RT (p < 0.0001), but there was no difference at later time points. These results indicate that the increased risk for complications after surgical procedures are not directly related to changes in skin perfusion and microvascular responsiveness observed after postmastectomy RT.

Revisions after trapeziometacarpal joint resection arthroplasty: A systematic literature review.

BACKGROUND: The aim of this systematic literature review was to describe current indications and interventions for revisions after trapeziometacarpal joint (TMJ) resection arthroplasty. METHODS: The literature search was conducted by an experienced librarian in the Medline, EMBASE, Cochrane Library, Web of Science and Scopus databases. We included all articles that investigated any TMJ arthroplasty procedure in which the trapezium was completely resected and if any subsequent revision procedure including joint-related and soft-tissue surgeries was mentioned. Two independent reviewers selected the articles and were involved in data extraction. RESULTS: Sixty-two articles reporting on 5,284 operated thumbs and 434 revision surgeries were included. We extracted 24 indications for revision and 31 revision techniques. Most revisions were performed because of subsidence/impingement of the first metacarpal bone (n=194 thumbs) followed by unspecified pain (n=53), metacarpophalangeal joint problems (n=28) and scaphotrapezoidal osteoarthritis (n=17). Eleven treatment strategies were found for subsidence/impingement of the first metacarpal, the most frequent being revision of the existing interposition using autologous tendon (n=46) and soft tissue interposition with distraction pinning (n=28). CONCLUSIONS: There are a wide variety of indications and even more surgical techniques described in the literature to treat persisting or recurrent pain after TMJ resection arthroplasty. Currently, there is no uniform treatment guideline available how to diagnose and treat such cases. Therefore, the results of this literature review will form the basis for a Delphi study aiming to develop recommendations for the diagnosis and treatment of persistent / recurrent pain after TMJ resection arthroplasty. LEVEL OF EVIDENCE: IV.

Diagnostic and treatment recommendations for recurrent or persistent symptoms after trapeziectomy: a Delphi study.

The aim of this Delphi study was to provide a diagnostic and treatment algorithm for patients with persistent or recurrent symptoms after trapeziometacarpal joint resection arthroplasty. Three Delphi rounds were conducted in which surveys were sent to 182 experienced hand surgeons worldwide. Responses were received from 140 participants. A consensus threshold was set at 67% agreement. Diagnostic tools and treatment approaches for six common revision scenarios achieved consensus. Radiographs are appropriate as primary (97%) and CT scans as secondary (76%) diagnostic tools. For scaphometacarpal impingement, 67% of respondents agreed that revision interposition is appropriate, with 93% recommending autologous tendon for the interposition. Additional suspension was considered appropriate by 68% of the participants. The diagnostic and treatment algorithm can help the surgeon to identify the reason for persistent symptoms after trapeziometacarpal joint resection arthroplasty and to choose an appropriate treatment strategy.Level of evidence: V.

Learning curves in Motec total wrist arthroplasty: an international cohort study.

We examined the learning curve of Motec total wrist arthroplasty (TWA) of six experienced surgeons in their first 30 cases. Three times more complications/revisions were encountered in the first half of the study compared with the second half. Motec TWA surgery should be concentrated in a smaller number of centres performing higher volumes.

Complication rates and modes of short and medium-term failure in Motec total wrist arthroplasty: an international cohort study.

The aim of this study was to analyse the short- and medium-term complications of the Motec total wrist arthroplasty (TWA). Identifying exact modes of failure and their causes should allow surgeons to avoid or mitigate these risks in the future. Retrospective analysis of prospectively collected data from six hand surgeons at five international centres provided details of 171 Motec TWAs. The mean follow-up was 5.8 years (range 18 months to 12 years). There were 33 (19%) complications within our cohort, with a revision rate of 8.2% (14 revisions). There was no difference in complication rates between metal-on-metal and metal-on-polymer articulations. Failure of osseointegration was the most common complication. Problems with soft tissue balancing, implant impingement related osteolysis, bony impingement and metacarpal fracture were found to be other preventable causes of failure in this series. Elimination of these preventable complications will improve survival rates for this implant.Level of evidence: IV.

Correlation between Indocyanine Green Fluorescence Angiography and Laser Speckle Contrast Imaging in a Flap Model.

Background: Indocyanine green fluorescence angiography (ICG-FA) is used to assess tissue intraoperatively in reconstructive surgery. This requires an intra-venous dye injection for each assessment. This is not necessary in laser speckle contrast imaging (LSCI); therefore, this method may be better suited for tissue evaluation. To determine this, we compared the two methods in a porcine flap model. Methods: One random and one pedicled flap were raised on each buttock of six animals. They were assessed with LSCI at baseline, when raised (T0), at 30 minutes (T30) and with ICG-FA at T0 and T30. Regions of interest (ROI) were chosen along the flap axis. Perfusion, measured as perfusion units (PU) in the LSCI assessment and pixel-intensity for the ICG-FA video uptake, was calculated in the ROI. Correlation was calculated between PU and pixel-intensity measured as time to peak (TTP) and area under curve for 60 seconds (AUC60). Results: Correlation between LSCI and AUC60 for the ICG-FA in corresponding ROI could be seen in all flaps at all time points. The correlation was higher for T0 (r=0.7 for random flap and r=0.6 for pedicled flap) than for T30 (r=0.57 for random flap and r=0.59 for pedicled flap). Even higher correlation could be seen PU and TTP (T0: random flap r=-0.8 and pedicled flap r=0.76. T30: random flap r=-0.8 and pedicled flap r=0.71). Conclusion: There is a correlation between PU from LSCI and TTP and AUC60 for ICG-FA, indicating that LSCI could be considered for intraoperative tissue assessment.

Rehabilitation following flexor tendon injury in Zone 2: a randomized controlled study.

The aim of this study was to compare an early active motion (EAM) regimen to a modified Kleinert passive motion therapy in Zone 2 flexor tendon injuries with regards to range of motion (ROM), grip strength and patient-reported outcome measures (PROMs). Seventy-two patients were included. At 3 months postoperatively, we found no difference in total active motion (TAM) between the EAM and the Kleinert groups (median 195.5°, range 115°-273° versus median 191.5°, range 113°-260°), but a significantly better grip strength (median 76%, range 44%-99% versus median 54%, range 19%-101%; p < 0.0005) in the EAM group. Disabilities of the Arm, Shoulder and Hand (DASH) score as well as patient-reported weakness, cold intolerance and problems in daily activities also favoured the EAM group. At 12 months postoperatively, there was no difference in TAM, grip strength or any of the PROMs used. We conclude that EAM leads to a quicker recovery in terms of grip strength and PROMs, but that both regimens lead to similar results at 12 months.Level of evidence: I.

Patient-reported outcome measures and their association to the original Strickland classification after flexor tendon repair.

The aim of this study was to examine the relationship between patient-reported outcome measures (PROMs) and the original Strickland classification after flexor tendon injuries in Zones 1 and 2. Data were collected from the Swedish national health care registry for hand surgery (HAKIR). The studied PROMs were the Quick Disabilities of Arm, Shoulder and Hand (QuickDASH) and the patient questionnaire from the HAKIR (HQ-8). Complete data of both range of motion (ROM) and PROMs were available for 215 patients at 3 months after surgery, and for 150 patients at 12 months after surgery. We found that QuickDASH values were low and similar between all groups as classified by the Strickland system at 12 months. A statistically significant difference between PROM values (for stiffness and satisfaction) was found only between the Strickland groups Fair and Good, but not between Poor and Fair or Good and Excellent. This suggests that further categorization according to the Strickland classification is less important to the patients as long as they regain 70% of their ROM.Level of evidence: III.

Insights and trends review: artificial intelligence in hand surgery.

Artificial intelligence (AI) in hand surgery is an emerging and evolving field that will likely play a large role in the future care of our patients. However, there remain several challenges to makes this technology meaningful, acceptable and usable at scale. In this review article, we discuss basic concepts in AI, including challenges and key considerations, provide an update on how AI is being used in hand and wrist surgery and propose potential future applications. The aims are to equip clinicians and researchers with the basic knowledge needed to understand and explore the incorporation of AI in hand surgery within their own practice and recommends further reading to develop knowledge in this emerging field.

Dynamic assessment of the upper extremity: a review of available and emerging technologies.

The purpose of this review article is to provide an update on the realm of emerging technology available for the assessment of dynamic functional movement of the hand and upper limb. A critical overview of the literature and a conceptual framework for use of such technologies is proposed. The framework explores three broad purpose categories including customization of care, functional surveillance and interventions through biofeedback strategies. State-of-the-art technologies are described, from basic activity monitors to feedback-enabled robotic gloves, along with exemplar trials and clinical applications. The future of technologies innovation in hand pathology is proposed in the context of the current obstacles and opportunities for hand surgeons and therapists.

Distal ulna fractures in adults-subcapitular, transverse fractures did not benefit from surgical treatment.

INTRODUCTION: Fractures of the distal ulna, excluding the styloid, are rare. The cause of injury is often a fall on an outstretched hand with an extended wrist, and in most cases there is a concomitant distal radius fracture. The aims of this retrospective study were to investigate the results of the current treatment of distal ulna fractures in adults, with or without a concomitant distal radius fracture, and if a recently presented fracture classification could predict outcome. MATERIALS AND METHODS: Patients, 18 years or older, treated for a fracture of the distal third of ulna in our county, were included. Fractures of the styloid tip were excluded. The radiographs of the fractures were independently classified by two specialists in radiology according to the 2018 AO/OTA classification. Follow-up was performed 5-7 years after the injury, through the questionnaire Patient-Rated Wrist Evaluation (PRWE) and new radiographs of both wrists. RESULTS: Ninety-six patients with 97 fractures were included and filled out the PRWE. 65 patients also had new radiographs taken. 79 patients were women and the mean age at the time of injury was 63 years (SD 14.5). The most common fracture class was the extra-articular transverse fracture, 2U3A2.3 (42%). We found that 40% of the fractures had been treated by internal fixation and only 2 fractures had not healed, one conservatively treated and one operated. The median PRWE was 15 (IQR 33.5). The PRWE score was significantly worse in the operated ulna fractures (p = 0.01) and this was also true for extra-articular transverse fractures 2U3A2.3 (p = 0.001). Initial displacement was more common in operated transverse fractures, but it could not be proven that this was the reason for the inferior result. CONCLUSIONS: Distal ulna fractures almost always unite and the result is comparable to that of isolated distal radius fractures when measured by PRWE. Based on the opinions of the radiologists and how often a consensus discussion was needed for classification, we found the updated AO classification system difficult to use, if dependent only on standard radiographic views. In the present study, transverse extra-articular ulna fractures did not benefit from internal fixation regardless if associated with a distal radius fracture or isolated.

Risk factors for reoperation after flexor tendon repair: a registry study.

The aim of this study was to identify risk factors for reoperations after Zones 1 and 2 flexor tendon repairs. A multiple logistic regression model was used to identify risk factors from data collected via the Swedish national health care registry for hand surgery (HAKIR). The studied potential risk factors were age and gender, socio-economics and surgical techniques. Included were 1372 patients with injuries to 1585 fingers and follow-up of at least 12 months (median 37 IQR 27-56). Tendon ruptures occurred in 80 fingers and tenolysis was required in 76 fingers. Variables that affected the risk of rupture were age >25 years (p < 0.001), flexor pollicis longus tendon injuries (p < 0.001) and being male (p = 0.004). Injury to both finger flexors had an effect on both rupture (p = 0.005) and tenolysis (p < 0.001). Understanding the risk factors may provide important guidance both to surgeons and therapists when treating patients with flexor tendon injuries.Level of evidence: III.

Basic science approaches to common hand surgery problems.

The field of hand surgery is constantly evolving to meet challenges of populations with increasing age and higher demands for active living. While our surgical care has improved over the last decades, it seems that future major improvement in outcomes of clinical treatment will come through advances in biologics and the translation of major discoveries in basic science. This article aims to provide an update on where basic science solutions may answer some of the most critical issues in hand surgery, with a focus on augmentation of tissue repair.

Investigation of proteins important for microcirculation using in vivo microdialysis after glucose provocation: a proteomic study.

Insulin has metabolic and vascular effects in the human body. What mechanisms that orchestrate the effects in the microcirculation, and how the responds differ in different tissues, is however not fully understood. It is therefore of interest to search for markers in microdialysate that may be related to the microcirculation. This study aims to identify proteins related to microvascular changes in different tissue compartments after glucose provocation using in vivo microdialysis. Microdialysis was conducted in three different tissue compartments (intracutaneous, subcutaneous and intravenous) from healthy subjects. Microdialysate was collected during three time periods; recovery after catheter insertion, baseline and glucose provocation, and analyzed using proteomics. Altogether, 126 proteins were detected. Multivariate data analysis showed that the differences in protein expression levels during the three time periods, including comparison before and after glucose provocation, were most pronounced in the intracutaneous and subcutaneous compartments. Four proteins with vascular effects were identified (angiotensinogen, kininogen-1, alpha-2-HS-glycoprotein and hemoglobin subunit beta), all upregulated after glucose provocation compared to baseline in all three compartments. Glucose provocation is known to cause insulin-induced vasodilation through the nitric oxide pathway, and this study indicates that this is facilitated through the interactions of the RAS (angiotensinogen) and kallikrein-kinin (kininogen-1) systems.